1. Field of the Invention
The subject invention relates to a one-piece aluminum heat exchanger tank and a method for fabricating such a tank.
2. Description of the Related Art
Various heat exchanger tanks exist in the art that are formed from a single sheet of metallic material. These one-piece tanks are typically fabricated by rolling an aluminum-clad sheet into a structure having integrally formed sidewalls and then joining two opposed side edges of the walls together along a common joint. The resulting tank is then connected to a core subassembly using conventional nuts and gasket seals in combination with discrete mounting brackets that must be positioned on the tank before the tank is connected to the core.
An example of a one-piece aluminum tank which utilizes separate mounting brackets for mounting the tank to a radiator core is disclosed in U.S. Pat. No. 6,167,953 (“Kobayashi et al.”). The Kobayashi et al., tank features a cylindrical body formed by brazing opposed end edges of an aluminum sheet together to form a joint that extends along the length of the tank. Specifically, one of the end edges of the joint overlaps the other on the exterior surface of the tank.
Although forming a single, overlapping joint on the exterior of the Kobayashi et al., tank arguably reduces the number of steps required to fabricate the tank, it does nothing to minimize the space occupied by the tank once it has been connected to a core subassembly. It also creates a rough, marred exterior surface which is so uneven that it renders the tank unuseable. Furthermore, the process of connecting the tank to the core is complicated by the use of the discrete mounting brackets. Each bracket must be separately brazed to the exterior of the tank before the tank can be attached to the core. Given the recent attention focused on creating an aluminum radiator that eliminates the header crimp area between the core and tanks, the marred surface created by overlapping the mounting brackets and exterior joint of the Kobayashi et al., invention fails to provide a suitable solution for minimizing the space occupied by a one-piece header tank.
Although Kobayashi et al., and other references specifically disclose aluminum tanks having brazed joints and which are mounted onto cores using separate brackets, the references fail to provide any type of connecting joints that are strong, yet result in a tank having a space-saving and smooth exterior surface. The references also do not disclose a tank featuring such a joint in combination with an integrally-formed bracket or rail for use in connecting the tank to a core.